Refrigeration



July 4, 1939.

G. G RUBB REFRIGERATION Filed June 16, 1936 INVENTOR.

kw ATTORNEY.

Patented July 4, 1939 UNITED STATES PATENT OFFICE REFRIGERATIONApplication June 16, 1936, Serial No. 85,481 In Germany June 20, 19351'1 Claims.

My invention relates to refrigeration, and more particularly toapparatus for maintaining an enclosed space substantially at a desiredtemperature with the aid of refrigeration apparatus operated by heat.

The object of my invention is to provide an improved apparatus formaintaining an enclosed space substantially at a desired temperaturewith the aid of heating means and refrigeration apparatus operated byheat.

Another object of my invention is to provide such apparatus formaintaining an enclosed space substantially at a desired temperature inwhich the refrigeration apparatus, after not .5 being in operation,shall be effective to cool the enclosed space in the minimum length oftime after the operation of the apparatus is initiated.

Further objects and advantagesof my invention will become apparent fromthe following de- 30 scription taken in connection with the accompanyingdrawing in which Fig. 1 is a diagrammatic illustration of an embodimentof my invention for heating an enclosed space and refrigerationapparatus operated by heat with gas 35 burners; and Fig. 2 is afragmentary sectional view of a modification of parts of the embodimentshown in Fig. 1.

Referring to Fig. 1 of the drawing, I have shown a cooling element l0and a heater ll ar- 30 ranged within an enclosed space l2, such as, for

example, the thermally insulated storage compartment of a refrigeratorcabinet l3. It is to be understood, however, that other arrangements ofa cooling element and a heater can readily be 35 made for maintaining anenclosed space substantially at a constant or desired temperature.

The cooling element Ill forms part of refrigeration apparatus comprisinga generator l4 containing a refrigerant in solution in absorption liq-;0 uid. Although I do not wish to be limited therei to, the refrigerantmay be ammonia and the absorption liquid may be. water. A main gasburner I5 is disposed below the generator and projects its flame l5 intothe lower end of a flue l6 which 45 extends upward through thegenerator. The heat applied to the generator and its contents by themain gas burner l5 expels the ammonia out of solution, and the ammoniavapor thus generated flows upward through an air cooled rectifier I1 50which condenses any water vapor which may be carried upward with theammonia vapor. The water condensed in the rectifier drains back to thegenerator, and the ammonia vapor flows upward to an air cooled condenser18 comprising a 55 coil provided with a plurality of heat dissipatingelements, or cooling fins l8. The ammonia is liquefied in the condenserill by surrounding cooler air which flows over the surfaces of the coiland fins, and the liquefied ammonia flows through a conduit l9 into aconduit 20 communicating 5 with one end of the evaporator or coolingelement II], the conduit l9 being U-shaped at 2| to provide a liquidseal.

The cooling element l0 may comprise a coil (not shown) arranged within ashell 22 provided with trays 23 for freezing water. An inert gas, suchas hydrogen, flows from a conduit 24 and enters the end of the coolingelement opposite to that into which liquid ammonia is admitted. Thehydrogen and liquid ammonia are in counterflow, therefore, and theammonia evaporates and diffuses into the hydrogen with consequentabsorption of heat from the surroundings of the cooling element in thestorage compartment l2. The resulting gas mixture of ammonia andhydrogen, that is, gas strong in ammonia, fiows from the cooling elementI!) through conduit 20 which communicates at its lower end into thelower end of an absorber 25 comprisingan enclosed vessel provided with acoil 26 through 25 which a suitable cooling medium, such as water, maybe circulated.

The ammonia is absorbed out of the strong gas mixture into weakabsorption liquid which enters. the upper part of the absorber through averti- 80 cally extending conduit 21. The absorber may be provided witha plurality of distributing plates or bafiles (not shown) to insure theabsorption of ammonia into the weak absorption liquid, and

the hydrogen, which is practically insoluble and weak in ammonia, passesupwardly from the absorber 25 through conduit 24 into the coolingelement Ill. The conduits 20 and 24 are preferably in thermal contact orheat exchange relation, as diagrammatically shown in Fig. 1, so thatheat is transferred from weak gas entering the cooling element throughconduit 24 to the strong gas leaving the cooling element through conduit20. The absorption liquid flowing downward through the absorber 25 incounter-fiowto the gas mixture becomes enriched in ammonia and passesthrough conduit 28 and an inner conduit 29 of a liquid heat exchanger 30to a coil 3| disposed about the lower end of flue IS. The strongabsorption liquid is heated in the coil 3| by the main gas burner I5 andis raised by thermo-syphon action from the coil through conduit 32 intothe upper part of the generator [4. The absorption liquid is raised to ahigher level in the generator l4 than it is in the absorber 25, and

absorption liquid weak in ammonia flows from the lower end of thegenerator through a conduit 33, outer conduit 34 of the liquid heatexchanger 30 and vertical conduit 21 into the upper end of the absorber25. Refrigeration apparatus of the above type is generally described inPatent No. 1,609,334 to B. G. von Platen and C. 'G. Munters.

The heating means for the enclosed space I2 comprises an auxiliaryburner 35 which is at right angles to the burner I5. The flame 35' ofthe burner 35 projects into the conical shaped lower end 36 of a flue 31which extends vertically upward through the refrigerator cabinet I3 andconstitutes the heater II to which are secured a plurality of heatdissipating elements or fins 38. The upper end of the flue 31 may beenlarged and provided with a plurality of baflles 39 which may be soregulated that they prohibit the downward flow of air surrounding thecabinet and are automatically opened thermostatically in a suitablemanner in response to the temperature of hot gases rising in the flue31. Similar baffles maybe arranged at the lower end of the flue 37 if itshould be desirable in certain instances to prohibit the flow of airinto the lower end of the flue when the burner 35 is not being operatedto heat the enclosed space I2.

During normal operation of the above-described refrigeration apparatus,heat must be applied to the generator I4 and its contents at or above apredetermined rate by the main burner I5 in order to heat therefrigerant to its vaporization temperature or boiling point sothatrefrigerant will be vaporized and expelled out of solution from theabsorption liquid. When the enclosed space l2 tends to fall below thedesired temperature and heat is no longer applied" to the generator, thegenerator and its contents are cooled by the surroundings. Subsequently,when the enclosed space tends to rise above the desired temperature andthe operation of the refrigeration apparatus is again initiated, heatmust be applied to the generator I4 and its contents by the main burnerI5 for a relatively long period of time before refrigerant is heated toits vaporization temperature and expelled out of solution from theabsorption liquid.

In accordance with my invention, in order to reduce the time thateffective cooling is obtained after operation of the refrigerationapparatus is initiated, the main burner I 5 and auxiliary burner 35 areso arranged and controlled that, during a heating period of the enclosedspace I2, the application of heat to the generator is not discontinuedbut modified to apply heat to the generator at such a rate that heat ofliquid is supplied to the refrigerant to heat the refrigerant to atemperature slightly below its vaporization temperature. In this manner,when a heating period is terminated and the operation of therefrigeration apparatus is again initiated, the refrigerant is heated toits vaporization temperature in a relatively short time and the coolingelement In is effective substantially immediately to maintain theenclosed space at the desired temperature.

This may be accomplished by conducting a suitable combustible gaseousfuel from a-source of supply (not shown) through a. conduit 40 to anadjustable pressure regulating valve M which reduces and maintainssubstantially constant the pressure of the gas supplied to the gasburners I5 and 35. From the pressure regulating valve 4| gas flowsthroughconduit 42 to the main burner I5, and through parallel conduits43 and 44, casing 45 and conduit 46 to the auxiliary burner 35. Withinthe casing 45 is arranged a valve 41 which is connected to an expansiblebellows 48. The expansible bellows 48, tube 49 5 and thermal element 50in the enclosed space I2 contain a volatile fluid and constitute anexpansible fluid thermostat for closing and opening the valve 41 with anincrease and decrease in temperature, respectively, of the enclosedspace 10 I2. The operation of the apparatus just described issubstantially as follows: v When the enclosed space I2 tends toriseabove the desired temperature the expansible fluid thermostat causesthe bellows 48 to expand and close the valve 41. With the valve 4!closed only a small quantity of gas flows through conduit 43, theleft-hand chamber of the casing 45 and conduit 46to the burner 35. Thissmall quantity 20 of gas is delivered to the burner 35 to provide apilot or ignition flame for the burners when the burner 35 is not beingemployed for heating the flue 31. With the valve 4! closed, the greaterportion of gas flows through conduit 42 to the main burner I5, and themain flame I5 applies heat to the generator I4 at or above apredetermined rate which is effective to heat the refrigerant to itsvaporization temperature or boiling point and expel refrigerant out ofsolution from the absorption liquid. After the operation of therefrigeration apparatus has thus been initiated the cooling element Ineffectively acts to cool the enclosed space when cooling is necessary tomaintain the enclosed space I2 at the desired temperature. When theenclosed space I2 tends to fall below the desired temperature theexpansible fluid thermostat causes the expansible bellows 48 to contractand open the valve 41, thereby varying the proportion of fuel deliveredto burners I5 and 35. Thiswill permit gas to flow through the conduit 44as well as through the conduit 43 to the burner 35, and the flame 35'becomes larger so that it will project into and heat the flue 31 whenheating is necessary to 45 maintain the enclosed space I 2 atthe desiredtemperature. When the auxiliary flame 35 increases in size the mainflame I5 becomes smaller, due to the fact that the pressure regulatingvalve 4| maintains the pressure of the gas delivered to the burners I5and 35 substantially constant. The conduits 42, 43 and 44 are sodimensioned that, when the auxiliary burner 35 is being operated to heatthe flue 31, the size of the main flame I5 is such that heat will besupplied to the generator I4 below the predetermined rate to heat therefrigerant toa temperature slightly below its vaporization temperature.When the operation of the refrigeration apparatus is again initiated tocool the enclosed space I2, the length 0 of time required to bring therefrigerant to its vaporization temperature will be relatively small.

In Fig. 2 I have shown a modification of parts of the apparatusillustrated in Fig. 1 for controlling the delivery of gas to the burnersI5 and 5 35. The valve 5| shown in Fig. 2 may be employed'as a pressurereducing valve and interposed between the conduits 42 and 46 of theburners I5 and 35, respectively, and the main gas delivery conduit 40.The valve 5I comprises 70 a valve body 52 provided with a doubleconicalshaped chamber 53 which is cylindrical in any section, the upperand lower surfaces 54 of which are truncated. From the diametricallyopposite sides of thecylindrical chamber 53 extend two due to theheating thereof while the enclosed passages 55 and 56 which communicatewith conduits 42 and 46, respectively. The main gas delivery conduit 40is connected to the valve body 52 and communicates With the chamber 53at the lower truncated surface thereof.

Within the chamber 53 is arranged a cylindrical body 51 which is in theform of a double truncated cone, the flat cylindrical surfaces 58 ofwhich are somewhat smaller in diameter than the corresponding truncatedsurfaces 54 of the chamber 53 in order to permit slight horizontalmovement of the body 51 within the chamber 53. The conical-shapedsurfaces of the body 51 are ground so that they will fit accuratelyagainst the conical-shaped walls of the chamber 53 when the body 51,which is connected by a rod 59 to the expansible bellows 48 of theexpansible fluid thermostat, is moved either to the left or right inresponse to the temperature of the enclosed space to regulate the mannerin which gases are delivered through the passages 55 and 56 to theburners l and 35, respectively.

The body 51 is provided with two small vertical passages Eli and BIwhich communicate at their lower ends with the main gas conduit 40. Thepassage 6!] has a right angle bend and the horizontal portion thereof isarranged to communicate with the passage 55 irrespective of the positionof the body 51 in the chamber 53. The upper end of the passage 6|communicates with a horizontal passage 62 which extends to diametricallyopposite points in the upper conical surface of the body 51. Gas willflow from the passage 52 either into the passage 55 or the passage 55,depending upon the position of the body 51 within the chamber 53. Withthe body 51 in its extreme left-hand position, as shown in Fig. 2, thepassage 62 is closed to supply gas through the passage 56 and conduit 46to the burner 35, and both the passages 60 and 62 are open to delivergas through the passage 55 and conduit 42 to the main burner 15. Thepassages in the valve 5| are so dimensioned that, under theseconditions, the main flame 15' will supply heat at or above thepredetermined rate which will heat the refrigerant to its vaporizationtemperature or boiling point and expel the refrigerant out of solutionfrom the absorption liquid.

When the enclosed space tends to fall below the desired temperature, theexpansible fluid thermostat will cause the expansible bellows 48 tocontract and move the body 51 in the direction of the arrow to theopposite side of the chamber '53. In this new position of the body 51the passage 62 is closed to supply gas through the passage 55 andconduit 42 to the main burner 15, and is opento deliver gas through thepassage 56 and conduit 46 to the auxiliary burner 35. The burner 35 willthus be effective to heat the flue 31 and maintain the enclosed space I2at the desired temperature. Although the delivery of gas to the passage55 is blocked 01f at the passage 62, gas is still delivered through thepassage 60, passage 55, and conduit 42 to the main burner I5. The sizeof the main flame I5 is therefore decreased during the heating of theenclosed space I2 and effective to supply heat to the generator at sucha rate that the refrigerant is heated to a temperature slightly belowits vaporization temperature. When the body 51 is subsequently moved tothe position shown in Fig. 2, the main flame l5 will again be increasedin size and ef fective to bring the refrigerant to its vaporizationtemperature in a relatively short period of time space was being heated.

While I have shown and described several embodiments of my invention,such variations and modifications are contemplated as fall within thetrue spirit and scope of my invention, aspointed out in the followingclaims.

What is claimed is:

1. Apparatus for heating and cooling a space comprising a refrigerationsystem including a heat receiving part and a cooling element, meansincluding said cooling element for cooling the space when said heatreceiving part is heated at or above a predetermined rate, meansincluding a heater for heating said heat receiving part and the space,and means for rendering said heater operative to heat said heatreceiving part at or above the predetermined rate when it is desired toeffect cooling of the space, and for rendering said heater operative toeffect heating of the space when it is desired to heat the latter, saidlast-mentioned means rendering said heater operative to heat said heatreceiving part belowthe predetermined rate while the space is beingheated so that, when said heater is again rendered operative to heatsaid heat receiving part at or above the predetermined rate, the lengthof time required to effect cooling will be reduced.

2. Apparatus for'heating and cooling a space comprising an absorptionrefrigeration system including a generator and a cooling element, meansincluding said cooling element for cooling the space when said generatoris heated at or above a predetermined rate, means including gas burnersfor heating the space and said generator, means including a valve andconduits connecting said valve and said burners for delivering acombustible fuel to said burners, said valve controlling the quantity offuel supplied to said burners, and means for rendering said valveoperative to supply fuel to said generator burner to heat said generatorat or above the predetermined rate when it is desired to effect coolingof the space, and for rendering said valve operative to supply fuel tothe other of said burners to effect heating of the space when it isdesired to heat the latter, said-valve and said conduits being soconstructed and arranged that fuel is supplied to said generator burnerto heat said generator below the "predetermined rate while the space isbeing heated so that, when said generator is again heated at or abovethe predetermined rate, the length of time required to effect coolingwill be reduced.

3. Apparatus for heating and cooling a space comprising an absorptionrefrigeration system including a generator and a cooling element, meansincluding said cooling element for cooling the space when said generatoris heated at or above a predetermined rate, means including two fuelburners for heating said generator and the space, respectively, andmeans for rendering one of said burners operative to heat said generatorat or above the predetermined rate when it is desired to effect coolingof the space, and for rendering the other of said burners operative toeffect heating of the space when it is desired to heat the latter, saidlast-mentioned means rendering said generator burner operative to heatsaid generator below the predetermined rate while the space is beingheated so that, when said generator burner is again rendered operativeto heat said generator at or above the predetermined rate, the length oftime required to effect cooling will be reduced.

4. Apparatus for heating and cooling 2. space comprising an absorptionrefrigeration system including a generator and a cooling element, meansincluding said cooling element for cooling the space when said generatoris heated at or above a predetermined rate, means including burners forheating the space and said generator, means including a'valve andconduits connecting said valve and said burners for delivering acombustible fuel to said burners, said valve controlcomprising anabsorption refrigeration system ling the proportion of fuel supplied toeach of said burners, and means for rendering said valve operative tosupply fuel to said generator burner to heat said generator at or abovethe predetermined rate when it is desired to effect cooling of thespace, and for rendering said valve operative to supply fuel to theother. of said burners to effect heating of the space when it is desiredto heat the latter. 5. Apparatus for heating and cooling a' spacecomprising an absorption refrigeration system including a generator anda cooling element, means including said cooling element for cooling thespace when said generatoris heated at or above'a, predetermined rate, aheating flue in heat transfer relation 'with the space, means includingburners for heating said generator and said flue, and means forrendering one of said burners operative to heat said generator at orabove the predetermined rate when it is desired to effect cooling of thespace, and for rendering the other of said burners operative to heatsaid flue when it is desired to effect heating of the space.

6. Apparatus for heating and cooling a space comprising an absorptionrefrigeration system ineluding a generator and a cooling element, meansincluding said cooling element for cooling the space when said generatoris heated at or above a predetermined rate, means including gas burnersfor heating said generator and the space,

respectively, means including a valve and conduits connecting said valveand said burners for K delivering a combustible fuel to said burners,

said valve controlling the quantity of fuel'supplied to said burners,and means for rendering said valve operative to supply fuelto saidgenerator burner to heat said generator at or above the predeterminedrate when it is desired to effect cooling of the space, and forrendering said valve operative to supply fuel to the other of saidburners to effect heating of the space when it is desired to heat thelatter, said valve and said conduits being so constructed and arrangedthat fuel is supplied to said generator burner to heat said generatorbelow, the predetermined rate while the space is. being heated and thatfuel is supplied to said other burner to maintain a pilot flame whilesaid generator is being heated.

7. Apparatus for heating and cooling a space including a generator and acooling element,

means including said cooling element for cooling the space, meansincluding burners arranged to heat said generator and the space,respectively,

- means including a valve and conduits connecting said valve and saidburners for delivering a combustible fuel to said burners, said valvecontrolling the proportion of fuel supplied to each of said burners,said valve being operative to permit fuel to be supplied to saidgenerator burner to heat said generator .when it is desired to effectcooling of the space, and also operative to. permit fuel to be suppliedto the other of said burners when it is desired to effect heating of thespace,

and said valve and said conduits being so constructed and arranged thatfuel is always supplied to one of said burners to maintain an ignitionflame.

8. Apparatus forheating and cooling a space comprising refrigerationapparatus including a heat receiving part having a flue and a coolingelement in heat transfer relation with said space,

a heating flue in heat transfer relation with said space, a commonsource of combustion gases for said flues, and means to vary theproportion of gases flowing in said flues.

9. Apparatus for heating and cooling a space as defined in claim 8, inwhich said means to vary the proportion of gases flowing in said fluesis automatically responsive to temperature.

10. Apparatus for heating and cooling a space comprising a refrigerationsystem including a heat-receiving part and a cooling element arranged tocool said space, a source of heated fluid, means -to,fiow heated fluidfrom said source in thermal contact with said heat receiving part,

' means to flow heated fluid from said source in heat transfer relationwith said space to be space, said last-mentioned means being constructedand arranged to permit continuous flow of heated fluid to said heatreceiving part and intermittent flow to said space.

11. Apparatus for heating and cooling a space comprising a refrigerationsystem operated by heat and having a cooling element to cool said space,means including a single heater arranged to heat said system to producecooling of said space and also arranged to heat said space, and means tovary the quantity of heat from said heater which is utilized to heatsaid system and said space, respectively, to control the temperature ofsaid space, said last-mentioned means being constructed and arranged topermit continuous heating of said system and intermittent heating ofsaid space.

GUNNAR GRUBB.

